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介孔炭作为加氢脱硫催化剂载体材料的研究 总被引:1,自引:0,他引:1
以介孔硅SBA-15为模板,焦糖和呋喃醇为碳源,通过多种浇注法制备介孔炭材料.采用低温氮吸附、透射电镜和X射线小角衍射分析模板及介孔炭的织构.结果显示合成的介孔炭成功地复制了SBA-15的结构.以制备的介孔炭作载体担载钴钼合成了加氢脱硫催化剂,利用X射线能谱、透射电镜能量分布谱及一氧化氮化学吸附评估了催化剂的活性及活性点分布,结果表明介孔炭担载的催化剂活性高于活性炭担载的同类催化剂. 相似文献
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在无外加酸体系中改变晶化温度合成Al SBA-15介孔材料,并以此为刚性模板,蔗糖为碳源,合成出一系列具有不同孔结构的有序介孔炭材料CMK-3,系统考察晶化温度对Al SBA-15和其反相复制结构CMK-3孔道结构的影响。结果显示在无外加酸合成体系中改变晶化温度可对Al SBA-15的孔道结构进行有效调控,通过结构复制技术可制备出具有不同结构的CM K-3。控制刚性模板Al SBA-15的晶化温度为90℃,所得介孔炭材料CM K-3(CM K-3(90))结构最佳,除介孔排列高度有序外,还具有高比表面积(1688 m2·g-1)和大孔容(0.95 cm3·g-1)。另外,对CMK-3的微孔性质与刚性模板孔壁中的次级介孔结构的内在联系进行研究,发现调变刚性模板的晶化温度可以有效改善有序介孔炭材料CMK-3的结构性质。 相似文献
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有序介孔炭合成、改性及其对汞离子的吸附性能 总被引:1,自引:0,他引:1
以有序介孔硅基材料(SBA-15)为模板,内烯酸低聚物为前驱物合成有序介孔结构的炭材料(OMC),并以化学方法将含氮基官能闭嫁接在有序介孔炭的表面.利用扫描电子显微镜(SEM),透射电子显微镜(TEM),红外光谱(FT-IR),X射线衍射(XRD)和氮气吸附-脱附(BET)对介孔炭进行表征.结果表明:表面改性后有序介孔炭的结构发生一定变化,但孔道特征仍保持二维六方有序性.合成的有序介孔炭及经乙二胺表而改性后胺化有序介孔炭的比表而积、平均介孔直径、平均孔容积分别为607 m2/g,4.1 nm,0.62 cm3/g和558 m2/g,3.8 nm,0.58cm3/g.对有序介孔炭及改性有序介孔炭进行的汞吸附实验,发现表面改性前后有序介孔炭对Hg(II)的吸附性能发生显著变化.嫁接胺基功能团后,其吸附容量增加一倍,表明胺基改性的OMC对汞有亲和作用. 相似文献
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利用浸渍法合成了Co3O4/SBA-15和CoFe2O4/SBA-15介孔纳米磁性材料, 并利用X射线粉末衍射(XRD)、 透射电子显微镜(TEM)、 场发射扫描电子显微镜(FESEM)及振动样品磁强计(VSM)对样品的微观结构和磁性能进行了分析。结果显示, Co3O4及CoFe2O4纳米颗粒分布在SBA-15介孔材料的孔道中, 可有效提高SBA-15介孔材料的磁性能。研究发现, SBA-15介孔纳米磁性材料的磁特性由掺杂的纳米磁性颗粒的性质决定, 其磁性能随Co3O4及CoFe2O4含量的增加而升高, 矫顽力可达400Oe, 饱和磁化强度达9emu/g。 相似文献
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镧(Ⅲ)对SBA-15分子筛改性研究 总被引:3,自引:0,他引:3
借助水热法,利用三嵌段共聚物聚(1,2-亚乙基二醇)-嵌段-聚(丙二醇)-嵌段-聚(1,2-亚乙基二醇)为模板剂,正硅酸四乙酯为硅源,强酸性条件下制备了分子筛SBA-15.分别以水及水+乙醇为介质采用LaCl3溶液与煅烧的主体材料SBA-15分子筛固-液相交换法,制备了La-(SBA-15)复合材料.利用化学分析、粉末XRD、N2吸附技术、IR评价了制备方法的有效性及对SBA-15分子筛孔结构的影响.结果表明,镧已并入SBA-15分子筛中,SBA-15内表面上的硅羟基团是镧进入的主要位置,部分客体在分子筛孔道内.制得的材料La-(SBA-15)保持高度有序的介孔二维六角结构,不改变载体SBA-15的介孔孔道结构.此外,考察了La-(SBA-15)产物的发光现象. 相似文献
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Fe3O4/壳聚糖磁性微球功能化SBA-15介孔分子筛的合成 总被引:1,自引:0,他引:1
通过反相悬液交联法制备出了Fe3O4壳聚糖磁性微球,以3-丙胺基三乙氧基硅烷(APTES)为硅烷偶联剂,采用后修饰法得到硅烷化SBA-15介孔分子筛.以戊二醛为交联剂将Fe3O4壳聚糖磁性微球接枝在硅烷化SBA-15介孔分子筛上.运用X射线衍射、傅里叶红外光谱等手段对Fe3O4壳聚糖磁性微球(MCS)接枝后的硅烷化SBA-15介孔分子筛进行了表征.分析结果表明,Fe3O4壳聚糖磁性微球通过硅烷偶联剂以化学键形式结合在SBA-15介孔分子筛上. 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.…… 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
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C. Qihong W. Zhan‐Wen J. Yi J. Yehua L. Fei F. Hanguang 《Materialwissenschaft und Werkstofftechnik》2014,45(7):582-590
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill. 相似文献
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Dimiter Hadjistamov 《材料科学与工程:中英文B版...》2019,(2):56-65
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ... 相似文献
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《中国标准化(英文版)》2014,(4)
正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from 相似文献
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《中国标准化(英文版)》2014,(5)
正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively. 相似文献